Smallness, portability, and convenience are the main trends in a portable electronic device design, such as electronic products like notebook computers, portable TVs, cell phones, or personal digital assistants (PDA).
FIG. 1 is a diagram illustrating a notebook computer in accordance with a prior art.
Traditionally, the case structure of a notebook computer, for example, the main parts of the notebook include a bottom case 102 which consists of the main frame of the notebook and a keyboard are sustained, and a cover case 104 with a display panel 101 that is associated in the bottom case 102. The bottom case 102 is pivoted on the cover case 104 by a hinge 103. The bottom case 102 and the cover case 104 must be opened apart from each other when the notebook is operated. When the notebook is idle, the bottom case 102 and the cover case 104 can be closed.
Generally, a latch structure is utilized to control the bottom case 102 and the cover case 104 to be opened or closed. The latch structure comprises a button portion 108 configured in the bottom case 102 and a latch 106 fixed on the cover case 104. When the bottom case 102 and the cover case 104 are closed, the latch 106 goes through a through-hole 110 located on the bottom case 102 to embed in the button portion 108, that makes the cover case 104 and the bottom case 102 engaged together.
When the latch 106 is released by pushing the button, the cover case 104 can be opened for operation. When the latch 106 is released, the cover case 104 is pushed by a spring element (not shown) settled in the hinge 103 that makes the bottom case 102 depart from the cover case 104 by disengaging the latch 106 from the through-hole 110. The cover case 104 then can be easily lifted to a suitable operation location.
However, the spring element of the hinge 103 sustaining the twist stress in operation is vulnerable to stress cracking, so that the hinge 103 must be operated under a restricted stress. Furthermore, the through-hole 110 located on the base case 102 can be plugged by debris such as dust, food or other undesirable materials when the latch 106 is disengaged. This debris can prevent the cover case 104 from engaging with the base case 102.